Adjustable and reversibly securable terrace stairs

ABSTRACT

Stair elements installed on sloped ground starting bottom up and using a riser reversibly secured with a clamping mechanism. Each riser is attached to a corresponding tread at the time of installation. The manner of fixing the riser to the tread permits the relationship between the two to be adjusted for angle and position.

BACKGROUND—FIELD OF INVENTION

[0001] This invention relates to exterior stairs, specifically terracedstairs used for landscaping customarily installed stair by stair inaccordance with the topography.

BACKGROUND—DESCRIPTION OF PRIOR ART

[0002] One of the traditional ways to make terrace stairs on slopedground is to lay a flat piece of rock or concrete as a starter tread atthe bottom of the slope where the stairs begin, and place one or morebarrier bricks at far end of the treads to form a riser, The area soformed is then back filled with soil and leveled even with the top ofthe bricks. The first stair tread is then placed thereon, and theprocedure repeated the next step and so on until the stairs reach thedesired height.

[0003] The method has the advantage that it permits the installer tovary the angle of incline to accommodate the slope within the rangebricks can be placed. For example, if the bricks that form the riseheight are placed at farthest end of tread, the incline is the smallest,as they are placed closer to the forward the incline becomes more.Moreover, the riser bricks can be placed with yaw angle so that thestair path follows the curvature of the slope.

[0004] A paramount disadvantage of this prior art methodology is thatthe soil has to be compacted against the inside of the riser surface.Since the riser is not secured, it is prone to disposition. Moreover,unsecured risers may also be subsequently displaced by use, erosionand/or other forces arising from changing climatic conditions.

[0005] One possible solution is to fabricate a combined structurewherein the riser is attached permanently to the tread. While compactingof the soil is greatly facilitated, there is a loss of flexibility inthat the incline becomes fixed and yaw angle is only adjustable byskewing the next tread against the installed riser, resulting in a lessaesthetic frontal appearance. Other obvious solutions suggested by theproblem involve adhesives such as cement to position the riser so as tobring about the desired incline and yaw angle during installation. Thishowever, necessitates delays in that work can progress only at a ratedetermined by the bonding time. Moreover, this approach does not allowfor correction once adhesion is complete. Another obvious alternative isto provide mechanical attachments (e.g., embedded bolts from the top ofthe riser adapted to fit into accordant holes in the treads). Thissolution too has obvious problems; the treads must have a number ofthreaded inserts to allow for adjustments, which are not only expensivebut also unsightly.

[0006] One prior art device marketed by American Concrete IndustriesCompany at 1022 Minot Ave. Auburn, ME 04210 the riser is attached to thefront-bottom of tread. In this design, the incline and yaw angle areadjustable by locating the next stair in desired place. But thisapproach also creates another problem, namely, the soil has to becontoured to fit the next stair while the next stair is not yet inplace—so there is an element of anticipatory fill making and compacting,which is much trial and error and labor intensive. A collateraldisadvantage of this product is due to its shape and bulk. Shipment andstorage require more space than separate steps and risers.

[0007] A fundamental disadvantage of all prior art structures is thatthey do not lend themselves to installation in open unbounded terrain.When installed in open slope without structures on both sides, rainerodes the soil adjacent to the stairs creating a ditch along bothsides. This can result in unsafe conditions, which are sometimes notobvious to persons using them.

[0008] Objects and Advantages

[0009] Accordingly, several objects and advantages of this inventionare:

[0010] (a) to provide stairs with risers that are adjustable in locationfor the incline and curvature of slope;

[0011] (b) to provide stairs that have a way to secure the adjustmentseasily and quickly once the adjustments are made so that the soil can beeasily compacted against the riser for integrity against the use andweather;

[0012] (c) to provide stairs that have a way to reverse securing ifcorrection has to be made;

[0013] (d) to provide a structure that facilitates the fill and level ofeach step against an already secure and adjusted step and riser;

[0014] (e) to provide stairs that are easily stacked for shipping andstorage;

[0015] (f) to provide a stair structure that reduces erosion by naturalelements.

[0016] Other objects and advantages of the invention will be apparentfrom a consideration of the drawings and ensuing description.

DESCRIPTION OF DRAWINGS

[0017] Both FIGS. 1 and 3 show only first and second stairs of possiblemany stairs. In the drawings, numbers with alphabetical suffixes arefeatures within those components.

[0018]FIG. 1 is upper right front view of the stairs with non-wingedriser with three components exploded to show the detail of theinterrelationship between the fit depicting the installation of risersin slight angle.

[0019]FIG. 2 is a view in detail of the part indicated by number 3 inFIG. 1.

[0020]FIG. 3 is upper left back view of stairs with winged risers andwith four components exploded to show how they fit together, it is alsodepicting the installation of riser in slight angle.

[0021]FIG. 4 is a view in detail of the assembly indicated by number 6in FIG. 3.

List of Reference Numerals

[0022]1 tread

[0023]2 non-winged riser

[0024]2 a spring clamp cavity

[0025]3 spring clamp

[0026]3 a clamp surface

[0027]3 b lead-in angle

[0028]5 winged riser

[0029]5 a riser portion

[0030]5 b wing portion

[0031]5 c clamp cavity

[0032]6 clamp assembly

[0033]7 bolt

[0034]8 clamp half

[0035]9 nut

DESCRIPTION OF A PREFERRED EMBODIMENT

[0036] A preferred embodiment of the invention is illustrated in FIG. 1with spring clamp 3 enlarged as shown in FIG. 2. The combination has atread 1, riser 2 and two spring clamps 3. Step 1 and riser 2 arepreferably concrete, rock or plastic; spring clamp 3 is preferably metalor plastic with sufficient spring force for having clamping surface 3 aand lead-in angle 3 b in each leg. Riser 2 has two spring clamp cavities2 a, one at each end. Spring clamp cavity 2 a is located such that thejaws of spring clamp 3 will have sufficient tension when spread apart soas to function as a clamp when forcibly positioned over the bottomsurface of tread 1 and upward surface of spring clamp cavity 2 a.Lead-in angle 3 b in each leg of spring clamp 3 eases the installationof it by providing starting slope for the spring. Clamping surfaces 3 awould be contacting two surfaces when installed. Riser 2 can thus beclamped to tread 1 in the desired location and yaw angle within thelimits of the structure.

[0037] A second preferred embodiment is shown in FIG. 3 with its clampassembly 6 enlarged as shown in FIG. 4. This combination has identicaltread 1 to that shown in FIG. 1, but the riser 5 and two clampassemblies 6. Are different. Clamp assembly 6 consists of a bolt 7, twoclamp halves 8 and a nut 9. Riser 5 is again preferably concrete, rockor plastic, clamp half 8 is preferably metal or plastic with sufficientstrength to carry out its function. Riser 5 consist of vertical portion5 a, wing portion 5 b integrally connected to riser portion 5 a at eachend, and two clamp cavities 5 c in the back surface of 5 a. Clampcavities 5 c are located such that riser 5 and tread 1 can be clampedtogether either from back or side of tread 1 so that riser 5 can beplaced at the desired location and yaw angle within the limits of thestructure. This embodiment provides additional protection againstrainwater erosion that tends to create ditches along both sides of thestairs. Because of winged portions 5 b, rainwater is channeled into thestairs so as to obstruct its free flow along the stair sides.

[0038] From the description above, a number of advantages are evident:

[0039] (a) The Riser position is adjustable in location and yaw angle sothat the stairs can be matched to the contour of the slope.

[0040] (b) Once the adjustment is done, the riser can be secured firmly,quickly and easily so that soil can be filled, compacted and leveled tothe top of the riser for robustness against the use and weather.

[0041] (c) Unlike securing the riser with permanent method like cementor adhesive, there is no waiting time for curing. Moreover, the positioncan be unsecured easily if correction has to be made.

[0042] (d) Installation is facilitated by a structural member thatallows direct preparation for the next stair requiring only fill andleveling of the soil against the riser, which is already adjusted andsecured.

[0043] (e) As per FIG. 1 and FIG. 3, the tread and riser are separaterectangular elements without protruding clamping components thusfacilitating convenient manufacturing, transportation and storage.

[0044] (f) For installations where erosion by rainwater is possible,these stairs have provisions to avoid this problem.

[0045] (g) All securing features become invisible once soil is filled;aesthetics are preserved.

[0046] Installation Procedure

[0047] In FIG. 1, first tread 1 is laid and leveled where the stairsbegin, riser 2 is placed according to the desired rise and desired curveto follow the slope, the riser 2 is fastened to tread 1 using springclamp 3, back of riser 2 is filled with soil and leveled to the top ofriser 2. Soil is then compacted and leveled against already securedriser 2. Tread 1 for the second stair is then placed on top of riser 2and the leveled soil and so on until the stairs reach the desiredheight. The stairs can end with ether a tread 1 or riser 2 depending onwhether there is a platform at the top of the stairs.

[0048] Stairs installed in open slope are susceptible to erosion; flowof rainwater would make ditches along both sides of the stairs. Theembodiment shown in FIG. 1 is preferable where erosion or otherstructures are not a problem. Installation of stairs in accordance withthe embodiment shown in FIG. 1 may also be preferable if the location isbetween existing structures, in which case riser 2 can be fastened totread 1 before they are put in place.

[0049] Installation in accordance with the embodiment shown in FIG. 3 issame as that described for FIG. 1 except for two factors. In FIG. 3 adifferent type of clamping device is shown, but in actuality they can beof the same configuration as that shown in FIG. 1. A second differenceis that soil has to be filled in the back and leveled to top of wingportion 5 so that water would not flow along both sides of stairs butflow into them to avoid creating ditches.

[0050] Summary, Ramifications, and Scope

[0051] Accordingly, the reader will understand that the adjustable andsecurable terrace stairs of this invention can be used to create stairsto fit the contour of slope easily and quickly. Moreover, they can beunsecured to make corrections yet they provide adequate integrityagainst use and weather because the riser is mechanically secured to thetread. Compacting of soil against that riser is easily done, so anunskilled worker can effect the installation. The parts can betransported and stored easily by stacking. And there is a provision thatreduces erosion along both sides of stairs by rainwater.

[0052] Although the description above contains specific embodiments,these should not be construed as limiting the scope of the invention butas exemplary only. For example, the clamping mechanism (either thespring clamp or the clamp assembly) can comprise any number of otherconfigurations, shapes and locking mechanisms. So too, can the risersand treads be fabricated to engage different configuration positions.Thus the invention should not be limited by the examples given, it beingunderstood that numerous changes, modifications and substitutions arepossible within the scope and spirit of the invention.

What is claimed is:
 1. An item of manufacture comprising: a first memberhaving an upper surface of length and width commensurate with thehorizontal dimensions of a stair tread; a second member having avertical surface of length and width commensurate with the dimensions ofa stair riser and wherein said second member has a lower edge adapted topermit it to be positioned relative to said upper surface of said firstmember whereby said upper surface of said first member forms a firststep and said vertical surface of said second member forms a riser for asecond step; Conditional fastening means for securing said second memberto said first member so as to permit each stair depth and yaw angle tobe adjusted during installation.
 2. The combination recited in claim 1wherein said second member includes at least one recess aperture, andwherein said conditional fastening means comprises: a U shaped springadapted to engage the underside of said first member and the recessaperture in said second member.
 3. The apparatus recited in claim 1wherein said second member has at least one opening, and wherein saidconditional fastening means comprises: a first L shaped bracket havingone leg positioned to fit within said opening in said second member; asecond L shaped bracket positioned to engage the undersurface of saidfirst member; means for pulling said first and second L shaped bracketstogether so as to clamp said first member to said second member.
 4. Aterrace stair system for adjusting the depth and angle of risersrelative to treads to comport with varying topologies comprising: riserpositioning means for temporarily fixing the depth of said treads inaccordance with the slope of the contour over which said system is to beinstalled; riser orientation means for temporarily fixing the yaw anglebetween tread and riser in accordance with the rotation of the contourover which said system is to be installed.
 5. The system recited inclaim 4 wherein said riser positioning means and said riser orientationmeans comprises: at least one retention means for engaging said risersat a fixed location and for temporarily engaging said treads at anylocation whereby the position and orientation of risers relative totreads may be varied to match the topographical contour.
 6. The systemrecited in claim 4 wherein said riser positioning means and said riserorientation means comprises: at least one retaining means for engagingsaid risers at a predetermined location and for engaging treads at alocation which can be altered to achieve different tread widths andorientations relative to said risers whereby said risers and treads maybe readjusted by altering the location where said retaining meansengages said treads.
 7. The apparatus recited in claim 6 wherein each ofsaid risers have recesses adapted to receive said retaining means, andwherein said retaining means includes elastic means adapted to engagesaid recesses and the undersides of said treads for exerting pressurebetween riser and tread whereby the position and angle of each of saidrisers with respect to each of said treads may be individually alteredby moving the location where said retaining means engages the undersideof said tread.
 8. A method of installing terrace stairs on variablecontours using identical flat treads and risers having openings on eachend adapted to receive a clamping apparatus comprising the steps of:laying a level first tread at the base of the slope; positioning a firstriser in accordance with the desired tread width, contour slope and yawangle; attaching a clamp to each end of said riser; securing each clampto underside of said first tread; backfilling against the backside ofsaid first riser; compacting the soil to level against said securedfirst riser; placing a second tread on top of said first riser andcompacted fill.
 9. A retaining mechanism for terraced stairs installedfrom separately fabricated risers and treads, comprising: attachingmeans for securing said risers and said treads as they are installed soas to position said risers orthogonal to said treads whereby said treadsform a horizontal stepping surface and said risers form a front supportfor another of said treads; repositioning means for varying the locationand angle of said risers relative to said treads to which they areattached while maintaining the orthogonal relationship there between.10. The apparatus recited in claim 9 wherein said attaching means andsaid repositioning means comprises: downward force exerting means forengaging said risers so as to pull the bottom edge of said risersagainst the upper horizontal stepping surface of said tread; upwardforce exerting means for engaging said treads so as to pull the upperstepping surface of said treads against the lower edge of said risers.11. The apparatus recited in claim 10 wherein said downward forceexerting means and said upward force exerting means comprise acompression clamp, and wherein said risers include connection means foroperatively mating with said clamp so as to permit the compressionclamping force to be transmitted to said risers so as to pull the bottomedge of said risers against the upper surface of said tread to which itis to be attached.
 12. The apparatus recited in claim 10 wherein saidupward force exerting means comprises one leg of a compression clampingmeans for provisionally engaging the undersurface of said tread at atrial location, whereby said upward force exerting means can be movedforward or backward relative to said undersurface of said tread in orderto modify the location of said riser relative to the upper steppingsurface of said tread.